This is our traditional reinforced kraft paper bitumen-bonded building paper laminate used within the construction industry, which meets the highest standard of BS 1521 materials, grade A1F. Unlike many other recent developments in building membranes (eg breathable roof underlays and air leakage barriers), BS 1521 does not give guidance on suitable use, and as such this product is a generic material,serving a wide range of end-user defined applications. However, typical usage for A1F has naturally evolved over time including for example, vapour checks, as an underlay on uninsulated cladding, flat lead-sheet underlay, timber floor DPM and temporary protection. Novia Ltd are the market leaders for building papers, so we can offer our expert guidance where required. Key Features: Bitumen, paper and reinforcement scrim laminate Suitable for permanent building applications Traditional product Standard roll sizes 1m x 25m and 1m x 50m Multi-use adaptable building product Typical uses: Vapour-checks Underlays on uninsulated cladding Temporary Protection Separation Layers Bond Breaks Draught and Damp exclusion Air Movement barriers Note: Novia products are non returnable if over or incorrectly ordered